Hello, I am not really sure how to figure this problem out, I don't see which formula to use in the text. Can you please let me know which formulas I would use to answer this question?

Common stock value: Constant growthMcCracken Roofing Inc. common stock paid a dividend of $1.20 per share last year. The company expects earnings and dividends to grow at a rate of 5% per year for the foreseeable future.a. What required rate of return for this stock would result in a price per share of $28?b. If McCracken expects both earnings and dividends to grow at an annual rate of 10%, what required rate of return would result in a price per share of $28?